lkml.org 
[lkml]   [2016]   [Jun]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] x86: prevent gcc from emitting SSE into boot code
On Wed, Jun 22, 2016 at 7:37 PM, Dmitry Vyukov <dvyukov@google.com> wrote:
> Latest gcc manages to emit MOVDQA into boot code
> which leads to crashes. Add more -mno-see flags.
>
> Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
> ---
> arch/x86/boot/compressed/Makefile | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
> index f135688..7eaafb8 100644
> --- a/arch/x86/boot/compressed/Makefile
> +++ b/arch/x86/boot/compressed/Makefile
> @@ -31,7 +31,7 @@ KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING
> cflags-$(CONFIG_X86_32) := -march=i386
> cflags-$(CONFIG_X86_64) := -mcmodel=small
> KBUILD_CFLAGS += $(cflags-y)
> -KBUILD_CFLAGS += -mno-mmx -mno-sse
> +KBUILD_CFLAGS += -mno-mmx -mno-sse -mno-sse2 -mno-sse3
> KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
> KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
>
> --
> 2.8.0.rc3.226.g39d4020


I withdraw this patch.

From off-list discussion:

"-mno-sse alone should disable all SSE/AVX instructions. If not,
please file a GCC bug report".

\
 
 \ /
  Last update: 2016-06-22 23:01    [W:0.038 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site